McClellan tied a career high and Mustafa Shakur added 21 points for Arizona (12-1, 3-0 Pac-10). The Wildcats are on their longest winning streak since they won 19 in a row in 1998 before losing in the NCAA regional finals to Utah.

Quincy Pondexter, benched for the first time in his collegiate career after 13 starts, matched his career high with 25 points for Washington (10-4, 0-3), which lost its third straight. He had scored 22 points in his three previous games combined.

Arizona won for just the third time in its last nine games against Washington. The Huskies had won their last seven home games against ranked opponents.

McClellan's fourth 3-pointer of the game gave Arizona a 70-69 lead with 11:38 left. After Ryan Appleby briefly gave Washington the lead back at 77-76 with a runner and pulled the Huskies within 87-86 with a fadeaway at the shot clock buzzer, McClellan responded with another 3. Arizona led 90-86 with 3:37 remaining.

Washington went the final 4:25 without a field goal. Appleby missed a wide-open 3 with 1:35 left that could have cut the Wildcats' six-point lead in half.

Washington tried two new starters following a 22-point loss at top-ranked UCLA on Sunday - freshman Phil Nelson and Appleby, a junior, with Pondexter and point guard Justin Dentmon going to the bench.

It worked for the first 32 minutes, anyway.

Washington burned through a 22-4 run over 6 1/2 minutes of the NBA-paced first half to go up 45-31 with Pondexter, who entered the game 3 1/2 minutes in, getting 10 points. Two of the baskets were spectacular: a spin between two defenders before a finger roll layup and a behind-the-back dribble in traffic and windmill lay in. Those had the roaring, sold-out crowd shaking 80-year-old Hec Edmundson Pavilion in anticipation of a reviving upset.

But much of that surge came with Shakur and Williams on the Arizona bench. When they returned, the Wildcats immediately answered with a 15-0 run to retake the lead on McClellan's second consecutive 3-pointer with 3 minutes left in the half. McClellan, who entered the game averaging 10 points in six starts, had 11 in the first half.

Pondexter scored four of Washington's final six points to put Washington back up 51-48 at the end of the frantic half, in which both teams shot just under 60 percent from the field.

Arizona coach Lute Olson did not substitute for the first 15 minutes of the second half, while his starters pushed back into the lead for good.